Screening of antimicrobial activities in red, green and brown macroalgae from Gran Canaria (Canary Islands, Spain)

Extracts from 44 species of seaweed from Gran Canada (Canary Islands, Spain) were screened for the production of antibacterial and antifungal compounds against a panel of Gram-negative and Grampositive bacteria, mycobacteria, yeasts and fungi. A total of 28 species displayed antibacterial activity, of which six also showed antifungal activity. Asparagopsis taxifonnis and Cynwpolia barbata were the species with the strongest activities against the broadest spectrum of target microorganisms. All the species with antibacterial activity were active against Gram-positive bacteria, whereas only two species, A. taxiformis and Osimmdea liybrida, were active against mycobacteria. The production of secondary metabolites with antimicrobial activities by the macroalgae was also studied under different conditions, although no common trend for bioactivity was observed. © Springer-Verlag and SEM 2001.